1. Field
The presently disclosed subject matter relates to a vehicle light fitting unit.
2. Description of Related Art
Conventionally, as a vehicle light fitting unit such as an automobile headlight, a vehicle light fitting unit in which two headlights which are provided parallel irradiate a low beam is proposed.
For example, as shown in FIG. 4A, each headlight 100 of the vehicle light fitting unit includes a light emitting element 102, an elliptical series reflecting surface 101, a projecting lens 104, and a light shielding member 103.
Among the above, the light emitting element 102 is formed in a rectangular flat plate shape elongated in the left and right direction, and is mounted on a circuit substrate 102A tilted to the rear.
The elliptical series reflecting surface 101 is formed in a concave shape open to the front of the light irradiating direction and is provided in a state in which a first focal position 101A is positioned near the light emitting element 102 and a second focal position 101B is positioned on the optical axis X of the headlight 100 so that light from the light emitting element 102 reflects to the front of the light irradiating direction.
The projecting lens 104 is provided on the optical axis X so that the focal position on the side of the rear of the light irradiating direction is positioned in the front of the area near the second focal position 101B.
The light shielding member 103 is provided lowered from near the second focal position 101B, shields a portion of the reflected light from the elliptical series reflecting surface 101 to the projecting lens 104 and forms a light distribution pattern including a boundary between light and dark (cut off).
In such headlight, after the image of the light emitting element 102 provided in the first focal position 101A is formed in the second focal position 101B, the image is projected forward by the projecting lens 104. However, the light reflected in the lower half section of the reflecting surface 101, in other words, the light projected forward and upward by the projecting lens 104 is shielded by the light shielding member 103 and does not reach the projecting lens 104. Therefore, the upward light is not included in the irradiating light of the vehicle light fitting unit and a low beam light distribution shape is obtained as shown in FIG. 4B or FIG. 4C. The diagrams are schematic diagrams showing a light distribution pattern formed on a virtual screen separated a predetermined distance to the front of the vehicle when the vehicle light fitting unit is for right hand traffic. The heavy line shows one of the headlights forming the light distribution (diffusion light distribution) in a relatively large area and the two dot chain line shows the other headlight forming the light distribution (concentration light distribution) in a relatively small area. Moreover, in the diagram, line H shows the line intersection between the horizontal plane which passes the optical axis X and the virtual screen and line V shows the line intersection between the vertical plane which passes the optical axis X and the virtual screen.
However, in the conventional vehicle light fitting unit, a clear cut off of the light and dark boundary is formed in the upper edge section of the light distribution and there is a problem that light above the cut off is not irradiated at all. Therefore, pitching of the vehicle occurs or in a situation where up and down of the road surface continues, it is difficult to see forward, danger avoidance action is delayed or the above becomes a reason of fatigue when driving. When forward and upward light is irradiated too much, this provides a blinding light to oncoming vehicles.